package com.atguigu.springcloud.lb;

/**
 * 版权声明 QZing 版权所有
 * 关联资源
 * 修订记录：
 * 1）更改者：
 * 时  间：2015-9-1
 * 描  述：创建
 */
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Component
public class MyLB implements LoadBalancer {

	private AtomicInteger atomicInteger = new AtomicInteger(0);

	//坐标
	private final int getAndIncrement(){
		int current;
		int next;
		do {
			current = this.atomicInteger.get();
			next = current >= 2147483647 ? 0 : current + 1;
		}while (!this.atomicInteger.compareAndSet(current,next));  //第一个参数是期望值，第二个参数是修改值是
		System.out.println("*******第几次访问，次数next: "+next);
		return next;
	}

	@Override
	public ServiceInstance instances(List<ServiceInstance> serviceInstances) {  //得到机器的列表
		int index = getAndIncrement() % serviceInstances.size(); //得到服务器的下标位置
		return serviceInstances.get(index);
	}
}